tonight and a giant, golden day for the american team. Gabby douglas soaring to a gold medal in the women's all-around competition and michael phelps added to his leggas. Just what you thought his story couldn't get any better, it did. Bill weir leading our coverage again tonight from london. Reporter: The greatest two hours of gabby douglas' life began with a vault. And it was better than anyone could have hoped. It put her at the top of the leader board, where she stayed through the flying squirrel playground on the uneven bars and through the balance beam, bending in lines so straight she makes architects jealous. She finished on the floor with a big grin and the unabashed love of the london crowd. But after russia's victoria komova wheeled out a stellar routine, gabby had to stare up at the scoreboard, heart in throat, until the numbers flashed a dream come true. First african american all-around champion, ever. But this brand of gold does not come cheap. She's been in love with tumbling since toddling, but as this online ad from pg shows, to train with the best, gabby had to leave her home in virginia beach and live with strangers in iowa. By her 16th birthday, the homesickness was unbearable. Mom refused to let her come home. Mom, you're supposed to be with me on this one. You're supposed to let the baby come home. She was, like, nope. Life is not easy. You have to fight and refuse to quit. Reporter: She didn't quit. And now that her air force staff sergeant dad is back from afghanistan, two families get to revel in the fruits of her gifts and grit. Meanwhile it was a liquid stage for the kind of leading-man duel we wait four years to watch. Conventional wisdom and newsstands full of beefcake covers said that this would be the race ryan lochte would use to take the greatest swimmer mantle from michael phelps. But phelps had something else in mind. For the third time in three olympics, america's aquaman won the 200 medley as lochte settled for silver. Meanwhile on the women's side, great day for rebecca soni, she wins the gold and sets a new world record in the process. As for athletes who stay dry while racing across water, the team usa women defended their beijing gold. Not everybody stayed dry. Cox and mary whippe gets tossed into the water as traditional celebration. The splash always to be expected.

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Gabby Douglas Wows in Olympic Gymnastics

The 16-year-old faced off against Russia's Viktoria Komova for the all-around title.